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Title: Nanoscale control of LaAlO3/SrTiO3 conductance beyond the polar catastrophe
Conductive atomic force microscope (c-AFM) lithography can be utilized to create a wide range of LaAlO3/SrTiO3 (LAO/STO)-based nanoelectronic devices in a reconfigurable manner. Experiments were generally performed with intrinsically insulating LAO/STO heterostructures, with LAO thickness less than the critical value at which a polar catastrophe takes place [<4 unit cell (u.c.)]. Here, we use inductively coupled plasma reactive ion etching (ICPRIE) to fabricate c-AFM “canvases” on intrinsically conducting LAO/STO samples with ≥4 u.c. LAO. We observe that its interfacial two-dimensional electron gas (2DEG) can be pinched off and then switched back on by c-AFM lithography. Nanowires created with initially conductive LAO/STO interfaces have an order-of-magnitude longer lifetime in ambient conditions, when compared to an identically created 3.4 u.c. LAO/STO nanowire. We also demonstrate key nanoscale properties such as ballistic transport in a quasi-one-dimensional electron waveguide at a 5 u.c. LAO/STO interface. This approach frees c-AFM-written nanodevice designs from time constraints in air associated with <4 u.c. LAO/STO heterostructures.  more » « less
Award ID(s):
2225888
PAR ID:
10633748
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
American Institute of Physics
Date Published:
Journal Name:
Journal of Applied Physics
Volume:
138
Issue:
9
ISSN:
0021-8979
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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